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International audience; A passive twist control is considered as an adaptive way to maximize the overall efficiency of a proprotor developed for convertible Micro Air Vehicles (MAV). In this paper, adaptation of the proprotor geometry in accordance to flight configurations is achieved by induced twist generated by the inherent structural coupling effect in anisotropic composite material and centrifugal force emanating from the tip load. Beam Finite Element Model based on Rotating Timoshenko Theory is used to predict structural loads, while Blade Element Momentum Theory is employed to predict the aerodynamic performance of adaptive proprotor as applied on Micro Air Vehicles (MAV). The iterative process of combination of aerodynamic model and structural model is used to compute the steady-state deformation of the flexible laminated proprotor blade due aerodynamic loads. Finally, the optimal design of lamina blade material is carried out to investigate the potential of flexible blade in the proprotorperformance enhancement.

Mechanical behaviors of pile-soil effect and anchor-soil effect are significantly important in supporting engineering activities of foundation pit. In this paper, finite difference method (FDM) was utilized to perform the numerical simulation of pile-anchor system, composed of supporting piles and pre-stressed anchor cables. Numerical simulations were on the basis of the foundation pit of Jinan's West Railway Station, and 3D simulation analysis of foundation pit has been prepared during the whole processes of excavation, supporting and construction. The paper also analyzed the changes of bending moments of piles and axial forces of cables, and discussed mechanical behaviors of pile-anchor system, through comparisons with field monitoring. The results show that the parameters concluding vertical gridding's number, cohesion of pile and soil, and pile stiffness have robust influences on supporting elements' behaviors. Mechanical behaviors of supporting pile and axial forces of anchor cable changed dramatically, indicating that the potential failure form was converted from toppling failure to sliding failure., 4th International Conference on Civil Engineering, Architecture and Building Materials, CEABM 2014; Haikou; China; 24 May 2014 through 25 May 2014, Applied Mechanics and Materials, 580-583, pp.238-242; 2014

The authors have developed a shark ray robotic fish based on biomimetic approaches. The paper describes the newly developed robotic fish technology and its application to mechatronics in the space. It is found that robotic fish technology creates not only new underwater robotics, but also the next generation space mechatronics for geological survey of lunar/planets and dust cleaning in the space station., 2013 the 3rd International Conference on Mechatronics and Applied Mechanics (ICMAM2013), Dec.27-28, 2013 Paris, France, Applied Mechanics and Materials, 527, pp.224-229; 2014

In this paper, a new simulation model is developed to be able to simulate diesel genset smart grid interconnection by keeping in view future requirements of the grids and grid codes. The simulations are carried out in Matlab/Simulink environment. An example case is based on 1200 kW variable speed diesel genset with permanent magnet synchronous generator (PMSG). The simulations are carried out for various dynamic behaviours of PMSG and their protection and control facilities, which are necessary in normal operating conditions and in a range of disturbed operating conditions in order to preserve or to re-establish system security. Various faults (e.g. disturbances) have been induced in the distribution system and the robustness of the network has been analysed to make sure continuous supply of electricity to the consumers in the future smart grid environment.

This paper describes a precision control method for a magnetic drive actuator used for the laser cutting to realize high speed and high accuracy machining. Firstly, a zero bias current method is applied to drive the electromagnets to achieve a high-precision and long-stroke of the actuator. Secondly, a compensation method of the zero point of the displacement sensors is presented to prevent the generation of the disturbance force produced by the elastic hinges. Finally, the positioning performance of the actuator is evaluated through experiments and the experimental results show that the actuator has a positioning resolution of the order of micrometer, a bandwidth greater than 130Hz, and a positioning stroke of 1mm.

To evaluate quantitatively the performance of cushioning materials, a cushion curve is indispensable. However, the desired cushioning effect may sometimes be absent when we use the cushion curve to design a transport package. In addition, to plot the cushion curve, massive dynamic compression tests are traditionally necessary. Thus, large amounts of labor and material resources are required. Therefore, we used expanded polyethylene and laminated-board cushion as test materials to represent typical cushioning materials, and proposed simplified performance evaluation methods based on certain dynamic compression tests. An analysis of the experimental results showed that to obtain a more accurate packaging design, the shearing effect must be taken into account when using the cushion curve; For both plastic and paper cushions, new proposed performance evaluation methods significantly reduce the number of dynamic compression tests needed to accurately evaluate an actual packaging design.

Sensors that detect the distance and the position of an object are used in a lot of fields. Among of them, the sensors that measure the shift value of an object are a large scale system, furthermore, an accurate mounting of these sensors is required. To solve these problems, this paper proposes an optical linear sensor using one-side frosted glass. This sensor can detect the position of the light irradiation point only by putting it directly on the target. For a parallel light, it is irrelevant to the distance between this sensor and the source of light because the size of light beam is unchanged according to the distance. This sensor assumes that the sensor’s surface irradiated roughly vertical with the light, and does not need a high accurate mounting. Therefore, it can be easily used.

Perceptions of image surface are very challenging work for computer vision. Human can amazingly expert at recognizing the reflective properties of surfaces of various materials which a robot can not do easily so far. Smoothly we can differentiate a shiny metallic sphere from the plastic sphere of similar dimensions and structure. In this paper, various image surfaces are analyzed according to various image statistics for robot vision systems. Identification of synonymous objects under various real-world illumination or other environments are very daunting task. However, this is very challenging and crucial for machine vision systems. Both statistical analyses and human evaluation by various subjects under rigorous illumination conditions, we find significant improvement in our analysis and emphasis the importance of statistical evaluation of surfaces for computer vision. Our findings clearly demonstrate that skewness has direct resemblance with the surface glossiness-level. Intensity histogram also shows crucial clue for surface analysis.